The present invention relates to a motor unit having a drive motor and a control portion for controlling the drive motor, and more particularly, to a type thereof particularly useful as a drive source for an industrial sewing machine.
In a conventional industrial sewing machine, an induction motor used as a drive motor is provided separately from a control portion which controls the drive motor. The drive motor and the control portion are respectively attached to a fixing portion of the sewing machine.
Further, in an industrial machine such as the sewing machine to which an operator is directly accessible for its operation, housings are attached to the fixing portion for housing respectively the drive motor, the control portion as well as a power transmitting system so as to avoid danger to the operator. These housings are made to have a mechanically high rigidity such as a product of a aluminum die-casting product, otherwise the housing may be released from the fixing portion if the housing is made from a mere metal plate.
Accordingly, the conventional industrial machine increases its own weight due to the respective provisions of the housings made by the aluminum die casting product. The increased weight of the machine will lower the transportation of the entire machine, and increases its cost.